Indirect heater for fluids



1952 G. o. KlMMELL ETAL INDIRECT HEATER FOR FLUIDS 2 SHEETS-SHEET 1 Filed April 30, 1949 nveniors Garman 0. K immell b. Llzenau w Jan. 8, 1952 Filed April 50, 1949 c. o. KIMMELL ET AL INDIRECT HEATER FOR FLUIDS 2 SHEETSSHEET 2 Znwefitor: Garman akimmeu lmrveg I1. Chenaul (Ittonieg:

Patented Jan. 8, 1952 INDIRECT HEATER FOR FLUIDS Garman 0. Kimmell and Harvey L. Chenault,

Oklahoma City,

Okla.,

assignors to Black,

Sivalls & Bryson, Inc., Kansas City, Mo., a corporation of Delaware Application April 30, 1949, Serial No. 90,732

Claims.

This invention relates to a heater for liquids, particularly petroleum oils, and has for its principal object to provide a heater of the indirect type including a shell for containing a heat transfer liquid which is directly heated by an immersion type fire chamber located within the central portion of the shell and surrounded with an immersed flow tube bundle through which the liquid to be heated is circulated.

Other objects of the invention are to provide a small compact heater which combines the safety feature of less fire hazard with conservation of size and material; to provide a heater having a shell and an internal heater removably supported by one end of the shell and a tube bundle supported within the shell and removable through the opposite end for facilitating inspection and field repair; to provide an indirect type heater which operates with. maximum eificiency without the use of bafiles; to provide a heater that is con-- servative of fuel used; and to provide a greater flow tube surface for a given size heater.

In accomplishing these and other objects of the invention, we have provided improved structure, the preferred form of which is illustrated in the accompanying drawings wherein:

Fig. l is a perspective view of a heater embodying the features of the present invention.

Fig. 2 is a perspective view of the firebox embodied in the heater.

Fig. 3 is a perspective view of the tube bundle which is employed in the heater to circulate the liquid to be heated.

Fig. 4 is a longitudinal section through the assembled heater.

Fig. 5 is an end view of the heater.

Fig. 6 is a cross section on the line 6-6 of Fig. 4, particularly illustrating the relation of the firebox and the tube bundle.

Referring more in detail to the drawings:

I designates a heater constructed in accordance with the present invention and which includes a cylindrical shell 2 that is arranged horizontally and supported on transverse girder plates '3 and 4 having laterally disposed flanges 5 and 6 by which the heater is adapted to be anchored on a suitable base. One end of the shell curves inwardly as at I to join with a coaxial collar 8 of suitable diameter for insertion of the firebox or heater unit 9, the collar 8 being provided with a laterally extending flange In for attaching a closure plate ll carrying the fire or heating unit as later described. The closure plate is secured to the flange ID by fastening devices such as bolts I2. The opposite end of the shell has an annularly 2 extending lateral flange I 3 for attaching a closure plate M which is secured to the flange byfastening devices such as bolts l5. The firebox or heating unit includes a pair of laterally disposed and horizontally disposed U-shaped ducts l6 and I! having upper and lower leg portions I8 and I9 welded in openings 23 and 2! that are provided in the plate H. The leg portions are of sufficient length to extend substantially to the opposite end of the shell and are interconnected by return bends 22. The upper legs I 8 are connected on the exterior side of the closure plate I l with a breeching 23 supporting a flue or stack 24 whereby products of combustion are discharged from the heating unit. The lower legs l9 project through the plate and are connected by a cap-like housing 25 having openings therein for supporting gas burners 2B and 21 in substantially concentric relation with the legs of the ducts, the burners being supplied with a fuel such as oil or gas through a supply pipe 28 which is connected through a pressure regulator 29 and an automatic control valve'30 with the respective burners, the valve 30 being actuated responsive to temperature within the heater to automatically regulate the fuel suplongitudinally positioned tubes 31 arranged in circular series about the supporting rings and which have opposite ends connected by return bends 38 and 39, the return bends at one end being staggered with respect to the return bends at the other so as to provide a continuous hairpin coil for conducting flow of a liquid to be heated. The

lowermost tubes comprise the terminals of the 'coil and the ends 40 and 4| extend through the closure plate I for connection With supply and discharge pipes 42 and 43, respectively, the connections being made by couplings as indicated at 44. a l

The shell is adapted to contain the heat transfer medium 3I, for example, water, which is inserted through a water equalizing pct 45 having a tubular neck 45 connected with the interior of the shell at the top thereof as best shown in Figs.

1 and 4, the pot 45 being of sufficient capacity to accommodate expansion of the transfer medium and to maintain the shell in completely filled condition. The top of the pot may be closed by a removable cover 41.

In assembling the heater, the tube bundle is inserted through the larger opening of the shell prior to application of the plate I4. After insertion of the tube bundle theplate I4 is bolted in leak-tight engagement with the flange I3. The heater or firebox has the leg portions thereof welded in the openings of the closure plate II and the upper legs I8 are interconnected by the breeching 23 which is also welded to theplate l l. The unit is 'then slid through the collar 8 so that the lower legs I9 of the fire ducts rest upon the supporting rings 33 and 34 and upon the segments 35 and 36 as shown in Fig. 6. When in position the closure plate H is connected with the flange ill by the bolts 12.

The burners 26 and 21 are then inserted and connected with a source of gas or other fuel. The supply and discharge pipes 42 and 43 are then connected with the terminal ends 40 and 4| of the coil by the couplings 44 so that the liquid such as a petroleum oil to be heated is passed through the hairpin coils of the tube bundle. The shell is then filled with a heat transfer liquid 3|, for example, water, which is supplied through the water equalizing pct 45. The-burners are started and the flame and hot gases travel through the legs of the U-shapedducts of the firebox to heat the surrounding water through the walls of the ducts. The products of combustion bring the water to a temperature set by the thermostat which afiects actuation of the control valve so that the burning rate is regulated to maintain the predetermined temperature of the heat transfer medium. As the water heats, a thermosyphon circulation is set up within the shell to effect substantially uniform heating of the tube bundle through transfer of heat from the walls of the firebox ducts to walls of the tube bundles.

When it is necessary to inspect or repair the heater the fire unit may be readily removed by removing the bolts l2 and withdrawing the unit from the collar 8 without disturbing th tube bundle. If the tube bundle is to be removed, this is readily effected by removing the bolts l3 which retain the plate l4 and by withdrawing the tube bundle through the open end of the shell.

From the foregoing it is obvious that we have provided an indirect type of heater which is of small, compact construction and combines the safety feature of less fire hazard with conservation of space and material. It is also obvious that the parts are readily assembled and removed as units for inspection and repair so that any repairs which may be required may be made in the field What we claim and desire to secure by Letters Patent is:

1. A heater including an elongated shell having open ends, removable closure plates for closing said ends of the shell and forming with the shell a closed heat-transfer-liquid-containing space, a heating unit carried by one of the closure plates and adapted to be inserted and withdrawn through the end of the shell closed by said one closure plate, a cylindrical tube bundle adapted to be inserted into the shell through the other end for encircling the heating unit, rings sup-porting said tube bundle and having inner circumferences to pass over the heating unit when inserted in the shell, and means for fillin said space with the heat transfer liquid for providing a common heat transfer medium between the heating unit and the tube bundle and completely surrounding the tube bundle and said heating unit.

2. A heater including an elongated shell having open ends, removable closure plates for closing said ends of the shell and forming with the shell a closed heat-transferliquidcontaining space, a heating unit carried substantially centrally of the shell by one of the closure plates and adapted to be inserted and withdrawn through the end closed by said one closure plate, a cylindrical tube bundle adapted to be inserted into the shell through the other end in coaxial relation with the shell and in encircling relation with the heating unit, means for filling said space with the heat transfer liquid for providing a common heat transfer medium between the heating unit and the tube bundle, said heating unit consisting of a pair of U-shaped ducts having ends extending through said carrying plate, a breeching connecting one end of each duct, and burners disposed in the other end of each duct.

3. A heater including an elongated substantially cylindrical shell having an open end conforming to the inner diameter of the shell and having a smaller axial opening at the other end, removable closure plates for closing said openings and forming with the shell a closed heattransfer-liquid-containing space, a heating unit carried by the closure plate for the smaller of said openings and adapted to be inserted and withdrawn through the smaller axial opening, a cylindrical tube bundle adapted to be inserted in the shell through the larger opening in encircling relation with the heating unit, means for filling the shell with the heat transfer liquid, said heating unit consisting of a U-shaped duct having ends extending through said smaller plate, a burner disposed in one end of the U-shaped duct, and a stack connected with the other end of the U- shaped duct.

4, A heater including an elongated shell having open ends, removable closure plates for closing said ends and cooperatin with the shell in forming a closed heat-transfer-liquid-containing space, a heating unit carried by one of the closure plates and adapted to be inserted and withdrawn through the end closed by said plate, an interconnected series of hairpin coils extending longitudinally within the shell and arranged in circular series about the interior of the shell and encircling relation to the heating unit, rings supporting said coils to form a unitary structure insertable and removable through the end of the shell which is closed by the other of said closure plates, and means for filling the shell with the heat transfer liquid to completely surround said units, said rings forming a support for the heater unit.

5. A heater including an elongated shell having open ends, removable closure plates for closing said open ends of the shell and cooperating with the shell in forming a closed heat-transferliquid-containing space, a pair of U-shaped ducts having ends fixed in one of the closure plates substantially centrally of said closure plate for sup- 'port centrally with respect to said shell, burners directed into the end of one leg of each of the ducts, a breeching connecting said other legs together, an interconnected series of hairpin coils extending longitudinally within the shell and arranged in circular series immediately adjacent the inner side of the shell, rings supporting said coils to form aunitary structure insertable and 5 removable through the end of the shell which is closed by the other of said closure plates, said rings having sliding support in the shell, and means for filling said space in the shell with the heat transfer liquid, said rings formin support for said legs of the ducts.

GARMAN O. KIMMELL. HARVEY L. CHENAULT.

REFERENCES CITED UNITED STATES PATENTS Number Number Name Date Thieble Apr. 24, 1900 Ripley Feb. 2, 1926 Priser Aug. 24, 1926 Carrol Aug. 8, 1933 La Mont June 23, 1936 Hanny Aug. 31, 1937 Walker et al Aug. 1, 1944 Arvins et a1 Oct. 10, 1944 Arvins et a1 Mar. 12, 1946 Barrett Sept. 9, 1947 Meixl Feb. 7, 1950 FOREIGN PATENTS Country Date Great Britain May 25, 1933 

